Reconfigurable Hyperbolic Polaritonics with Correlated Oxide Metasurfaces

Abstract

Polaritons enable subwavelength confinement and highly anisotropic flows of light over a wide spectral range, holding the promise for applications in modern nanophotonic and optoelectronic devices. However, to fully realize their practical application potential, facile methods enabling nanoscale active control of polaritons are needed. Here, we introduce a hybrid polaritonic-oxide heterostructure platform consisting of van der Waals crystals, such as hexagonal boron nitride (hBN) or alpha-phase molybdenum trioxide (α-MoO3), transferred on nanoscale oxygen vacancy patterns on the surface of prototypical correlated perovskite oxide SmNiO3 (SNO). Using a combination of scanning probe microscopy and infrared nanoimaging techniques, we demonstrate nanoscale real-time reconfigurability of complex hyperbolic phonon polaritons patterned at the nanoscale with unmatched resolution. Hydrogenation and temperature modulation allow spatially localized conductivity modulation of SNO nanoscale patterns, enabling robust real-time modulation and nanoscale reconfiguration of hyperbolic polaritons. Our work paves the way towards nanoscale programmable metasurface engineering as a new paradigm for reconfigurable nanophotonic applications facilitated by a hybrid material platform exploiting extreme light-matter interactions in polaritonic systems.

Enabling Active Nanotechnologies by Phase Transition: From Electronics, Photonics to Thermotics

“…With the galloping development of polariton-based nanodevices, how to actively control in-plane polaritons has become a new objective in the community. To date, many technologies have been proposed to modulate the polariton behavior, including twisting the angle between optical axes of two adjacent metasurfaces, ,− hydrogenation of the surface atoms, ,, and photoexcitation to inject electron–hole pairs . Nevertheless, these modulation methods are rather slow or only limited in specific materials.…”

“…By varying the length (metalens 1) and width (metalens 2) of each element to create the hyperbolic phase profile, focusing effects have been achieved of the two designed metalenses (Figure b­(iii) and (iv). This approach can be readily combined with other polaritonic vdW materials and other phase-change materials, , thereby enabling a whole range of deeply subwavelength and programmable polaritonic devices on-chip.…”